ESE's works engine tuner

[wobbly]

Helping is a pleasure Condyn . Interesting about your engine and class rules.
I had a short discussion some years back on another forum with a few people doing 440 champ engines , where I suggested that their Exhaust port ducts were way too big and the pipes
designed in, of all things Dynomation , were not even close to optimum.
This was greeted with howls of derision that I knew nothing about champ engine technology - and that i should stick to the toy 125s.

I did end up doing a paid in full EngMod sim project for one guy over there , and by doing exactly what i was told would not work , the sim showed something like 10% more peak Hp and a way greater gain 1000 rpm past that.
The conclusion was that the sim code was faulty , so being the complete arsehole i am I told them to fuk off and kept the new pipe design and the cash to myself - their loss not mine.
Funny to me that they were more pissed about me publishing their super secret , not so shit hot , pipe design than anything else.

The 350TZ LSR record holding engine that did 172mph stuck at 12,000 redline in 5th gear we were planning to go 200 this year , but way too hard making that happen with viruses running around even faster.

[andreas]

"Howls of derision" will of course result in a set of exquisite pipes- have we seen them here?

[yatasaki]

Regarding crankcase insulation, did an insulation with polyurethane foam on tomos centrifugal in-gearbox two speed engine. As the clutch is adjusted to slip between 7-8000 rpm (not only for starting but for pulling from corners)it produces certain heat apart from rest of the gearbox.Foam is applied in gearcase around crankcase and it works. Several checks were made for polyurethane being dissolved or detached but it is glued on place. No case temperature measurements were made before or after applying but one is certain, bike is faster than before for 200-300 revs on end of the straight.
Now a five speed gearbox case is being prepared for same foam application and case walls being made rough to keep oil longer attached for cooling..at least keeps my mind satisfied.

[Condyn]

RE 440 champ
The champ engine technology! The principles just will not apply here haha. With design limitations of being restricted to 1985 model cylinders which are air cooled, a champ engine is similar to what I am working on. Some builders now utilize engmod over here but many are stuck on the "end all be all" tom turner stuff. I have only one engine modeled as of now and am patiently waiting to get it on the dyno so I can further develop pipes in engmod. (This is not the engine I am constantly referencing.) As previously discussed I will need to find max power egt and possibly tweak the wall temps so the curves align with real life.
From what I have seen most of the Champ engines use a 198 degree exhaust duration with aux ports out to 100 percent creating a necessity for pin plugs. With the cvt we do not use much, if any, low rpm range. I still have trouble understanding the "why?" behind the large exhaust durations and blowdown sta when we do not exceed 11,000 rpm. It seems as if the pipes would have a hard time being utilized, yet it is seemingly (top secret) standard to see those numbers in champs.

[Peter1962]

Regarding crankcase insulation, did an insulation with polyurethane foam on tomos centrifugal in-gearbox two speed engine. As the clutch is adjusted to slip between 7-8000 rpm (not only for starting but for pulling from corners)it produces certain heat apart from rest of the gearbox.Foam is applied in gearcase around crankcase and it works. Several checks were made for polyurethane being dissolved or detached but it is glued on place. No case temperature measurements were made before or after applying but one is certain, bike is faster than before for 200-300 revs on end of the straight.
Now a five speed gearbox case is being prepared for same foam application and case walls being made rough to keep oil longer attached for cooling..at least keeps my mind satisfied.

This special insulation paint could be of interest for your project.
http://www.pit-lane.biz/t3173p760-gp...-part-2-locked

[wobbly]

Apart from the pipe ( that had a 2.1* included header angle ) hahahahahah , the numbers I was given meant the Transfer STA was at 76.5 Hp and the Blowdown was at 60.5.
But when I suggested that the Aux needed to go right around to bore center , and fit pin plugs , again I wasnt preaching to the converted as TSR and Dynomation said all was well.
A bit sad really - but hey they were " fast man , really fast " .

[andreas]

Stray sheep will find their way, not to worry.

[F5 Dave]

Stray sheep are delicious.

[andreas]

[Pursang]

Cylinder head for tm kz

Attachment 347635

Nostalgic bultaco engine

Attachment 347636

Bultaco had all sorts of chamber configurations available... and a dyno.

The bathtub ones probable sacrificed some combustion purity for better control of the scavenging charge and possibly heat distribution.
Some were then fitted with twin spark plugs to even up the combustion rate.

Cheers, Daryl

[SwePatrick]

Does someone have a typical 3d ignition map for twostroke and willing to share?
I need to see the 'shape', it tells me basics of what to think of when adjusting.

[lodgernz]

A recent faecesbook rant by disciple Cotswold, addressed to a non-believer:

"There is only one true faith, and you have your feet firmly on the path to damnation. Did not Jan Thiel say "behold here is a 2t and it is fast, strong and light", all that gazed upon it felt that power and put their knees on the floor and dragged them in delirium and once partaken of, the pull was unrelenting , did not Jan stand back and say "It is good" and it was. The fallen sat upon their misshapen rides with too many strokes, the failing of rods, the snapping of camchains and spilling of oil and they gnashed their teeth in anguish as yet another valve head detached itself to inflict more pain on the mistaken. There is only one true way, the way of the 2T. Braaap"

[breezy]

Max, the bore dimension on that drawing is "Ø 53,1 (Prelavorato)" which, as Google Translator will tell you, means raw, unfinished. The same goes for other dimensions in that drawing, like the exhaust port height and its center and corner radii. Besides, that drawing is quite an oldie; it doesn't show the RSA cylinder.

Patrick, the water temp in an Aprilia RSA125 is about 40°C (in the RSA250 it was about 50°C because otherwise the radiator size would have to be huge) but I'll admit that the cooling water is hotter than the surrounding air.
Following your reasoning, I should switch from watercooling to aircooling. Something tells me there has to be a catch. For example that a liquid will absorb heat a thousand times better than a gas, more than compensating for the smaller temperature difference between coolant and the object being cooled.

Frits,
would you think that modifying an air cooled barrel to be cooled with oil would be better than air? if your engine rules spec that " no WATER cooling allowed," and not "no LIQUID cooling allowed"... could this be a viable option?
regards, Nigel.

[wobbly]

Suzuki had the mainly oil cooled GSXR from 85 to 92.
The cylinders had tiny fins , as they ran two pumps. One high pressure for the usual bearing lube duty , the other circulated low pressure , high volume oil thru cooling galleries.
That system was dead reliable , and made for a very light weight engine assembly.

[husaberg]

Suzuki had the mainly oil cooled GSXR from 85 to 92.
The cylinders had tiny fins , as they ran two pumps. One high pressure for the usual bearing lube duty , the other circulated low pressure, high volume oil thru cooling galleries.
That system was dead reliable, and made for a very light weight engine assembly.

According to the net the dude that developed the system Suzuki later used on the GSXR750 (first made for the XN85 Turbo)
Estuo Yokouchi just copied off what they had done during WW2 for the high performance aero engines.
If what I found was correct some had the pump its self with low pressure and high-pressure outputs.
of course the advantage for Suzuki with the and the aero 4t was they had to have oil anyway.
what I remember most about all Suzuki's from that era was the smell of the cooked stators.
i am not sure which of the turbo bikes first had the under piston oiler jets as the ww2 planes did.
But the CX650T had the oilers as well.
Tom Sifton ran them in his Tuned Harley side valvers in the late40'searly 50's.
i have posted toms work here before not sure if it even mentioned I know the rotating lifters were
https://www.kiwibiker.co.nz/forums/s...post1130226221